# HG changeset patch
# User Jun Wu <quark@fb.com>
# Date 1489635792 25200
# Node ID 95be8b7181d36ee2da151117b9790b25ab5b24a2
# Parent  bc445c556d3c1cac13f14577878f1f902b4cf740
osutil: fix potential wrong fd close

According to POSIX closedir [1]:

  If a file descriptor is used to implement type DIR, that file descriptor
  shall be closed.

According to POSIX fdopendir [2]:

  Upon calling closedir() the file descriptor shall be closed.

So we should avoid "close(dfd)" after "closedir(dir)". With threads, there
could be a race where an innocent fd gets closed. But Python GIL seems to
help hiding the issue well.

[1]: http://pubs.opengroup.org/onlinepubs/009695399/functions/closedir.html
[2]: http://pubs.opengroup.org/onlinepubs/9699919799/functions/fdopendir.html

diff -r bc445c556d3c -r 95be8b7181d3 mercurial/osutil.c
--- a/mercurial/osutil.c	Thu Mar 09 12:09:31 2017 -0800
+++ b/mercurial/osutil.c	Wed Mar 15 20:43:12 2017 -0700
@@ -400,6 +400,8 @@
 	Py_XDECREF(stat);
 error_list:
 	closedir(dir);
+	/* closedir also closes its dirfd */
+	goto error_value;
 error_dir:
 #ifdef AT_SYMLINK_NOFOLLOW
 	close(dfd);